1.This product is the charging cable for Di2 series electronic shifting kit, only with charging function, not with data transmission function. 2. The product has a full power-off function, no need to worry about overcharging damage to the battery and the contrast is not energised, no need to worry about burning the transmission. 3. If the battery has been discharged, you need to use the original battery to activate it, otherwise there may be no response to full power transmission. 4. After connecting to the power supply, the green light is always on for full or inserted in reverse, the green light is always on and the red light is blinking or the red light is always on and the green light is blinking for charging. 5. If there is no response to the operation of the electronic speed change after charging, long any speed change key for 2s, after the indicator light is on, you can change the speed normally. Color: Black Material: plastic Package Contents: 1*road bike Battery Charger Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.